array (LaTeX environment)

LaTeX markup...	...results in:	...is used for:
\begin{array}{|l|cr} left1 & center1 & right1\\ \hline d & e & f \end{array}	${\begin{array}{|l|cr}left1&center1&right1\\\hline d&e&f\end{array}}$	array. |l|cr means left-align, center, and right align columns; vertical bars before and after first column. \hline draws a horizontal line.
\begin{array}{lcl} z & = & a \\ & = & a \\ f(x,y,z) & = & x + y + z \end{array}	${\begin{array}{lcl}z&=&a\\&=&a\\f(x,y,z)&=&x+y+z\end{array}}$	using an array to align equations

\begin{array}{|l|cr} left1 & center1 & right1\\ \hline d & e & f \end{array}